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arXiv · 0801.0627

Spin-charge Separated Solitons in a Topological Band Insulator

Ying Ran·Ashvin Vishwanath·Dung-Hai Lee
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Abstract

In this paper we construct a simple, controllable, two dimensional model based on a topological band insulator. It has many attractive properties. (1) We obtain spin-charge separated solitons that are associated with $π$ fluxes. (2) It suggests an alternative way to classify $Z_2$ topological band insulator without resorting to the sample boundary. (3) When the $π$ fluxes are dynamical variables, as in a correlated insulator with emergent gauge fluxes, these solitons are propagating bosonic excitations and their condensation triggers a phase transition into a planar ferromagnet.

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Ying Ran, Ashvin Vishwanath, Dung-Hai Lee. 2008-02-25. Spin-charge Separated Solitons in a Topological Band Insulator. https://doi.org/10.1103/physrevlett.101.086801

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